Audi 80 tdi juddering bucking jerking

[avanttdi]

Hello fellow judderers. As the creator of this thread i though id pop back and have a look at whats going on. It seems we have a couple of new members to the club. Welcome!

My car has covered 198k now and the last 5k of that has been done with the vss wire cut. It works a treat..you just have to go easy on and off the throttle because there is no active surge damping to smooth it all out.

So my advice to anybody with the problem: there are three ways of stopping it:

1. Pull fuse 12 under the bonnet...but this is no good because you lose other things aswell


2. Cut the wire behind the dash, but it seems you lose important lights then

3. The third way (and the one i would recommend) is to cut the blue and white vss wire just before it goes into the ecu in the pasenger footwell

meanwhile....if anybody wants to actually find the CAUSE of the problem, be my guest....happy hunting

[allan_audi]

The easiest wire to cut is behind the dash (remove the instrument cluster), the blue/white wire (pin 18) of the blue connector, this is the same wire that goes to the ECU. Its easier to access behind the dash. You shouldn't lose any lights, its just that cutting the wire causes an error in the ECU (loss of VSS signal) so you need to remove the CEL bulb otherwise it flashes endlessly and drives you mad!

[avanttdi]

thats weird...it didnt put my CEL on.......

[allan_audi]

thats weird...it didnt put my CEL on.......

Yeah that is strange, I've checked fault codes with VAGCOM and I have "loss of VSS signal", as you would expect.

[TDi-iac]

I have been driving with the juddering for around 25k now, and have not noticed any damage directly caused by that. A fair bit of work has recently been done in stages to the front quarters due to high mileage (205k) and each stage has reduced the juddering somewhat, implying it is an effect, rather than a cause of worn bushings, mounts, driveshafts etc..
There are a few little tricks to stop it immediatly but temporarily while moving, so I probably won't disable the vss signal.

[allan_audi]

thats weird...it didnt put my CEL on.......

Just as a matter of interest, does your yellow glow plug lamp come on at startup??

[allan_audi]

I have been driving with the juddering for around 25k now, and have not noticed any damage directly caused by that. A fair bit of work has recently been done in stages to the front quarters due to high mileage (205k) and each stage has reduced the juddering somewhat, implying it is an effect, rather than a cause of worn bushings, mounts, driveshafts etc..
There are a few little tricks to stop it immediatly but temporarily while moving, so I probably won't disable the vss signal.

Hi, I don't know how you can drive the car with the judder, mine is completely out of control in traffic and on slow roads. The slightest attempt at backing off the throttle and reapplying, the car goes into meltdown!! I have to keep dropping the clutch. I'm not sure what you're doing but I tried just about everything so far (we still don't know the cause as avanttdi points out), the only thing thats made it driveable is to do the VSS mod. Suspension bushes, engine, subframe mounts made little or no difference on my 80.

[avanttdi]

hi allan, yes my glow plug/cel light does come on when i turn the key for a few seconds, and then goes out as if the glowplugs have run their course...but i am well aware that the pre-heat stage of the glow plugs doesnt come on untill about minus four. The light does work properly, if i force the car into limp homme by unplugging something, the light will come on. But during normal daily use with the vss wire cut, it functions normally. Strange....

I reckon if all of us on here write to Audi they might do a delayed recall......lol

[TDi-iac]

Hi, I don't know how you can drive the car with the judder, mine is completely out of control in traffic and on slow roads. The slightest attempt at backing off the throttle and reapplying, the car goes into meltdown!! I have to keep dropping the clutch. I'm not sure what you're doing but I tried just about everything so far (we still don't know the cause as avanttdi points out), the only thing thats made it driveable is to do the VSS mod. Suspension bushes, engine, subframe mounts made little or no difference on my 80.

Depends on the speed you're going. Methods are let go the accelerator and gently re-apply; power through the judder by pushing about half way on the pedal; half applying the clutch for a *v* quick period while still accelerating (thankyou Audi for the extremely durable clutch plates!), or a quick gear change at slower speeds. In town conditions I have a habit leaving it in 5th at 30mph, so this last one isn't as bad as it sounds (you have to love the torque )
Although to be fair, with the age, my vs sensors do take a while to warm up (about 15 miles before accurate in the winter, 5 in summer) so this may help the predicament.

[skezzywooaudi80]

hi to all!! This thread has been very helpful to me.

I have a 1994 audi 80 1.9 tdi with the 1z engine and have suffered the same juddering problems for about a year so i tried disconnecting the wire behind dash and its all but gone just a little harsh if your rough with the throttle.

I`ve just joined this forum so i can ask if anyone has heard of the dual mass fly wheel which has been associated with juddering on diesel engines apparently its fitted to help quieten diesel engines down, i`ve never heard of these until about half an hour ago so if anyone knows if the audi 80 tdi has one of these fitted i would be greatful if you could let me know.

From what i can gather the newer 1.9tdi vw are fitted with them as are some other makes of cars, but not sure about older audi & vw models, i will have a look in my haynes manual to see if that sheds any light on the problem.

hope this will make sense to someone cheers andy!!